UPHESC Assistant Professor Genetics & Plant Breeding PYQs

Concept: J. H. Taylor, Woods and Hughes (1957) labelled root-tip chromosomes of Vicia faba with ³H-thymidine and showed by autoradiography that chromosomes replicate semi-conservatively.

1. Meselson & Stahl (1958) – E. coli, ¹⁵N/¹⁴N, CsCl gradient.
2. Cairns (1963) – autoradiography of E. coli chromosome (theta replication).

Short trick: Vicia faba + tritium = Taylor; E. coli + ¹⁵N = Meselson–Stahl.

Concept: R. H. Painter (1951, 'Insect Resistance in Crop Plants') classified the mechanisms of resistance as non-preference, antibiosis and tolerance.

1. Kogan & Ortman (1978) renamed non-preference as antixenosis.
2. Havens (1792) first reported Hessian-fly-resistant wheat, but did not propose mechanisms.

Short trick: Painter's triad: non-preference, antibiosis, tolerance.

Concept: Reproductive meristems (developing inflorescences, ovaries) do not transpire much and are hydraulically buffered, so at a given time their water stress is lower than in actively transpiring leaves.

1. Leaves lose water directly to the atmosphere and show the most negative water potential.
2. Yet reproductive stages are the most sensitive to drought, because even mild stress there disrupts pollen and grain set.

Short trick: Transpiring leaf = most stressed; meristem = buffered (less stress).

Concept: The first commercial multiline wheat was Miramar 63 (followed by Miramar 65), released in Colombia (1960s) from the Rockefeller-supported programme, based on Borlaug's multiline concept for rust resistance.

1. In India the first multiline wheats were KSML 3 (Kalyan Sona based) and MLKS 11 (1979–81).
2. Kalyan Sona and Sonalika are ordinary pure-line dwarf varieties from CIMMYT material.

Short trick: Colombia → Miramar 63; India → KSML 3.

Concept: Salicylic acid is a phenolic signal molecule (hormone) that induces PR proteins in systemic acquired resistance – it is not itself a protein.

1. PR-2 = β-1,3-glucanase; PR-3 (and 4, 8, 11) = chitinases; PR-5 = thaumatin-like proteins.
2. SA → NPR1 → PR gene expression → SAR.

Short trick: SA induces PR proteins; it is not one.

Concept: Heat tolerance is a complex quantitative trait (membrane thermostability, canopy temperature depression, grain filling, pollen viability, HSP expression) controlled by many genes – polygenic, with marked G × E interaction.

1. QTL for heat tolerance are numerous, each with small effect.
2. Hence it is improved by selection under stress, indices and genomic tools rather than single-gene transfer.

Short trick: Abiotic stress tolerance = polygenic.

Concept: In diploid B. campestris (B. rapa, AA genome) erucic acid is controlled by a single gene pair (FAE1 locus) with additive alleles; in amphidiploid B. napus and B. juncea two gene pairs (one in each genome) are involved.

1. Low-erucic (<2%) 'canola' quality needs the recessive (zero-erucic) alleles.
2. Embryo genotype (not maternal plant) determines erucic acid in the seed.

Short trick: Diploid campestris – 1 gene; amphidiploids napus/juncea – 2 genes.

Concept: Abscisic acid (ABA) accumulates under drought, salinity and cold; it closes stomata and induces stress-protective genes – hence the 'stress hormone'.

1. It also promotes dormancy and abscission; auxin, GA and cytokinin are growth promoters.

Short trick: ABA = stress & stomatal closure.

Concept: The National Seeds Project (Phase I) was launched in 1975 with World Bank assistance to build state seed corporations, seed processing plants and certification agencies.

1. Phase II – 1978; Phase III – 1990.
2. Related milestones: NSC 1963; Seeds Act 1966; Seed Review Team 1968; Seed Policy 1988.

Short trick: NSC 1963 → Seeds Act 1966 → NSP 1975.

Concept: The Patent Office has its head office at Kolkata, with branch offices at Delhi, Mumbai and Chennai; it works under the Controller General of Patents, Designs & Trade Marks (CGPDTM), whose office is in Mumbai.

1. GI Registry – Chennai; Trade Marks Registry head office – Mumbai; Copyright Office – New Delhi.

Short trick: Patent – Kolkata; GI – Chennai; TM – Mumbai.

Concept: India enacted its own sui generis law – the Protection of Plant Varieties and Farmers' Rights (PPV&FR) Act, 2001 – under TRIPS Article 27.3(b).

1. UPOV 1978 and 1991 are international conventions (Geneva); India is not a member of UPOV.
2. PPV&FR Authority was set up in 2005, New Delhi.

Short trick: India chose PPV&FR 2001, not UPOV.

Concept: Minikit trials: small packets of seed of promising/new varieties with a package of inputs are given to farmers and grown on farmers' fields to test adaptability and popularise them.

1. Station trials and multilocation (AICRP) trials are on research farms.
2. Minikits act as on-farm verification + seed spread.

Short trick: Minikit → farmer's field.

Concept: Darjeeling Tea was India's first Geographical Indication (GI) registered (2004–05) under the GI of Goods (Registration & Protection) Act, 1999.

1. GI protects goods whose quality/reputation is due to their place of origin.
2. GI Registry is at Chennai; GI protection lasts 10 years, renewable.

Short trick: First Indian GI = Darjeeling Tea.

Concept: Working collections are short-term stores (3–5 years) kept at 5–10 °C (<15 °C) with seed moisture around 8–10%, used by breeders for day-to-day work.

1. Active collections: medium term (10–20 yr) at about 0–5 °C, ~8% moisture – for evaluation, multiplication and distribution.
2. Base collections: long term (50–100 yr) at −18/−20 °C, 3–7% moisture.
3. Cryopreservation: −196 °C in liquid nitrogen.

Short trick: Working (short) → Active (medium) → Base (long) → Cryo.

Concept: UPOV 1991 (Article 19) gives a minimum protection of 20 years for crop (field) varieties and 25 years for trees and vines.

1. UPOV 1978: 15 years (18 for trees and vines).
2. India's PPV&FR Act: 15 years for field crops, 18 for trees/vines (registration valid 6/9 years, renewable).

Short trick: UPOV 91 → 20/25; UPOV 78 → 15/18.

Concept: Walter T. Federer (1956) introduced augmented designs – check varieties are replicated in blocks while new entries appear only once; checks give the error and block adjustment.

1. Ideal for early-generation breeding material with little seed.
2. Augmented RBD is the common form.

Short trick: Augmented = Federer (1956).

Concept: Σ(x − A)² is least when A = arithmetic mean (least-squares property).

1. Σ(x − A)² = Σ(x − x̄)² + n(x̄ − A)², minimum when A = x̄.
2. The sum of absolute deviations is least about the median.

Short trick: Squares → Mean; absolute values → Median.

Concept: In RBD, E(MS_genotype) = σ²_e + rσ²_g, so σ²_g = (MS_g − MS_e)/r.

1. MS_g − MS_e = 10.821 − 0.128 = 10.693.
2. σ²_g = 10.693 / 3 = 3.564.
3. (Phenotypic variance would be 3.564 + 0.128 = 3.692 – option D is the trap.)

Short trick: Vg = (Mg − Me)/r; Vp = Vg + Ve.

Concept: In a Latin square (t × t) each treatment occurs once in every row and every column, so number of rows = columns = replications = treatments.

1. It controls variation in two directions (double local control).
2. Usually suitable for 5–8 treatments.

Short trick: LSD: r = t (square!).

Concept: CRD uses only randomisation and replication; there is no blocking, i.e. no local control – suitable only for homogeneous material (lab/pot experiments).

1. RBD – one-way blocking; LSD – two-way; lattice – incomplete blocks.
2. Fisher's three principles: replication, randomisation, local control.

Short trick: CRD = no blocks = no local control.